You will not be able to see Agenda Fusion first instead of the default Microsoft Start view.

You can go to your favorite Agenda Fusion view quickly by assigning one of the hardware buttons on your Pocket PC to launch your favorite Agenda Fusion view. You can then press that button right after the Power button to go direct to your favorite AF view fast. To reassign a button ------

On your Pocket PC, go to Start/Settings/Buttons.

From the "Button" column, select the button that you would like to reassign.